Sex-related differences in the association between frailty and dietary consumption in Japanese older people: a cross-sectional study

BACKGROUND: Female sex is an important factor predisposing individuals to frailty. Appropriate nutrition is one of the most effective ways to prevent older adults from developing frailty; Sex-related differences have also been detected in the association between nutritional intervention and health-related outcomes. However, few studies have discussed these sex-related differences. The aim of the present study was to investigate the sex-related differences in the association between frailty and dietary consumption. METHODS: We conducted a cross-sectional study which investigated community-dwelling older adults aged ≥65 years. We surveyed age, sex, body mass index, family arrangement (living alone, living with a partner or living with parent(s) and/or child (ren)), dietary consumption and frailty status. Dietary consumption was surveyed using a food frequency questionnaire that included 13 major food categories (fish, meat, eggs, dairy products, soybean products, vegetables, seaweeds, potatoes, fruits, fats or oils, snacks, salty foods and alcohol). Frailty was defined by the Kihon Checklist score. The Kihon Checklist is composed of 25 simple yes/no questions, and it has been validated as a metric for frailty. A higher score indicates a greater degree of frailty. Multinomial regression analysis was performed to clarify the association between frailty and dietary consumption for each sex. RESULTS: We analyzed 905 older adults (420 (46.4%) were male). After adjusting for cofounders, a low frequency of meat consumption (less than twice/week) was associated with a high prevalence of frailty in men (odds ratio: 2.76 (95%CI: 1.12–6.77), p = 0.027). In contrast, in women, low frequencies of consumption of fish, meat, vegetables, potatoes and snacks were associated with a higher prevalence of frailty compared with those who consumed foods from those categories daily (odds ratios: fish 2.45 (1.02–5.89), p = 0.045; meat 4.05 (1.67–9.86), p = 0.002; vegetables 5.03 (2.13–11.92), p < 0.001; potatoes 3.84 (1.63–9.05), p = 0.002; snacks 2.16 (1.02–4.56), p = 0.043). CONCLUSIONS: More food categories were associated with frailty in women than in men. Nutritional intervention to prevent frailty is presumably more effective for women than for men. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12877-019-1229-5) contains supplementary material, which is available to authorized users.